There is a naked eye stereoscopic display which uses the integral photography (IP) technique and which has a parallax barrier using, for example, a pinhole, a slit or a lens array disposed on the display face side of an FPD (Flat Panel Display).
A pixel in the naked eye stereoscopic display includes an exit pupil and a plurality of subpixels on a FPD located behind the exit pupil. Pixel information acquired from a direction coupling the subpixels to the exit pupil is displayed on subpixels. As a result, it becomes possible for the viewer to perceive video information depending on the viewing position and positions of left and right eyes, and the viewer can perceive a solid. A set of pixel information displayed by taking subpixels corresponding to an exit pupil as the unit is called elemental image.
Since the number of pixels on the FPD is finite, the number of subpixels assigned to the exit pupil (which is equal to the number of parallaxes) also becomes finite, and the range of the elemental image which can be displayed is also restricted. Therefore, restrictions are imposed on a range in which a stereoscopic video can be seen and a depth which can be represented (depth representation range).
Therefore, the viewing zone can be widened by detecting a direction of the viewer and changing over a subpixel assigning an elemental image corresponding to the exit pupil to a subpixel viewed through the exit pupil. When changing over subpixels, pixel information displayed there is also changed over according to the illumination direction of the light ray. As a result, light rays required for the viewer to view a stereoscopic video are selected and reproduced.
There is a method for making the viewpoint interval narrower than the interval of light rays viewed from the FPD through the exit pupil when acquiring a multiple viewpoint image. A display object exceeding the depth representation range can also be crushed and displayed in the depth representation range by making the viewpoint interval narrow.
If the viewpoint interval of a multiple viewpoint image is made narrow, then the parallax of the image viewed by both eyes becomes small and a display object exceeding the depth representation range can also be crushed and displayed in the depth representation range. On the other hand, even if the viewing position moves horizontally, the side face cannot be seen readily (the motion parallax is small). In other words, as a result of suppressing the binocular parallax, the sacrifice of the motion parallax becomes great even in the case where the viewing zone is controlled.